Tuber Flesh Colour, Enzymatic Discolouration, Dormancy and Late Blight Resistance of 29 Tuber‑Bearing Accessions of Solanum spp.

Potato relatives adapted to many different habitats are promising sources of desirable
agricultural traits for potato breeding. Wild potato relatives are preserved in
different collections around the world, and their detailed description is key to their
exploitation in practice. We described 29 seed accessions of 26 Solanum species
originating from the VIR potato collection (Institute of Plant Industry – VIR, Saint
Petersburg, Russia) and preserved in Poland. The description included resistance to
Phytophthora infestans, tuber flesh colour, enzymatic discolouration and tuber dormancy
(sprouting). Up to 13 genotypes were evaluated per accession. The evaluation
was repeated in three years for each trait. Two P. infestans isolates were used
in late blight resistance tests. Amongst all the tested accessions, five were resistant
to both P. infestans isolates, including genotype 13_A2. Twenty-one accessions had
white tuber flesh, and 13 accessions showed a lack of or weak enzymatic discolouration.
Additionally, we found accessions that were whiter than the standard whitefleshed
Polish potato cultivar Irys. In our material, we observed a large variation in
the length of the sprouts after storage, indicating differences in the dormancy period
length. Four accessions showed a lack of sprouting after 28 weeks of storage at
5–6 °C. The tested material is preserved as in vitro plants in the National Centre for
Plant Genetic Resources: Polish Genebank (IHAR-PIB, Radzików, Poland), which
will facilitate their use in breeding programs.